What’s the Deepest hole we can possibly dig?

What’s the Deepest hole we can possibly dig? By David Grossman.

The limiting factor is almost always the temperature. The Kola was abandoned in 1992 when workers hit 356 degrees Fahrenheit [180 degrees Celsius], far hotter than they had anticipated. The tunnel was eventually closed off in the early 2000’s. While there doesn’t seem to be much interest in getting lower — the Kola helped discover microscopic plankton, which is nice but hardly inspiring like space.